Lech Walesa, the leader of Poland's independent labor federation Solidarity, today defended a compromise agreement with the communist authorities over workers' self-management in industry despite a storm of criticism from some union branches.

The issue of whether or not to endorse the compromise formula on the appointment of directors has split the delegates at Solidarity's national congress, which convened yesterday after a three-week break. Solidarity's 10-member national presidium has accepted the compromise and the Polish national assembly passed the law Friday.

During the first stage of the congress, an almost unanimous resolution was carried demanding that government and Solidarity plans for self-management be put to a nationwide referendum.

Today many delegates argued that Solidarity should go ahead with organizing its own referendum. But it seemed likely that a clear majority would vote to respect the compromise and call off the planned ballot.

Jan Rulewski, the Solidarity leader in the northern town of Bydgoszcz, said that the congress, as Solidarity's highest legislative body, had the right to overturn the decision of the union's national presidium. Delegates said a vote probably would be taken Monday.

A stormy debate on the issue could prove crucial in shaping the union's future strategy toward the government. First signs were that, partly as a result of the unprecedented propaganda drive by the Polish authorities and the Kremlin, the moderate group within Solidarity around Walesa has emerged strengthened.

Walesa told the delegates that although the new law was not perfect, the union was now in a position to make workers' self-management a reality in Poland. He said the government would retain the power to appoint directors in huge enterprises, but that in small and medium-size companies the workers would have the final say.

Some delegates argued that a confrontation with the authorities had only been postponed, since the two sides will now have to work out a list of strategic industries and public utilities where, according to the law, directors will be nominated by the relevant ministry. There could also be local conflicts because the law gives a power of veto over new appointments both to the government and the workers' councils.

Walesa said Solidarity should not attempt to destroy the existing system, since this raised the prospect of an even worse totalitarian state than before.

"It is not our role to try to overthrow the government. We must protect ourselves from ourselves," he said.

For the second day, huge crowds gathered outside the Olivia Sports Hall on the outskirts of Gdansk to hear the debates relayed by loudspeaker.

The harshest attack on Walesa's conciliatory policies came from Rulewski, the Solidarity leader who was beaten up by police last March. Referring to a string of official actions against Solidarity newspapers and the arrest of two union activists, he said it was useless to search for a compromise with the government under such conditions.

The course of today's debates suggested that, while the compromise decision is likely to be approved in the end by the full congress, there is a vocal minority of radicals in the union ready to attack the government on every issue possible.